1. Field of the Invention
The present invention relates to a video distribution system for distributing video data according to an authority of a client.
2. Description of the Related Art
Recently, a camera compatible with network has come to be widely used in various usages for the purposes of, for example, security and investigation used in, for example, residential districts, shops, banks, and stations. In order to avoid an invasion of privacy such as leakage of private information and confidential information in a photographic area, a camera capable of setting a privacy masking area in the photographic area for the sake of a viewing limitation is showing up in the market.
Conventionally, for example, Japanese Patent application Laid-open No. 2001-69494 discusses a technique that masking data for masking a privacy zone of which an image is displayed is stored to provide masking to a portion of the image according to the masking data.
However, continuity of video data received by a client who has no viewing authority with respect to the area with viewing limitation may be degraded depending on an instruction from a client having the viewing authority of the area with the viewing limitation.
A case that the area with the viewing limitation is a privacy masking area (hereinafter referred to as a masking area) is exemplified below. In this case, when the masking area is being set (moved or changed in size) by a client having the viewing authority, if video data is not distributed to a client who has no viewing authority, the continuity of the video data received by the client having no viewing authority may be degraded.
Also, a case that the area with the viewing limitation is an area outside a limited range of a panning angle and a tilting angle of the camera is exemplified below. In this case, when a client having the viewing authority is controlling the panning angle or the tilting angle beyond the limited range, if the video data is not distributed to a client having no viewing authority, continuity of the video data received by the client having no viewing authority may be degraded.